Valve unit for internal-combustion engines



Nov. 4, 1952 E. c. KIEKHAEFER 2,616,403

VALVE UNIT FOR INTERNAL-COMBUSTION ENGINES Filed July 29, 1948 2 SHEETS-SHEET 1 IN V EN TOR.

Nov. 4, 1952 E. c. KIEKHAEFER 6,

VALVE UNIT FOR INTERNAL-COMBUSTION ENGINES Filed July 29, 1948 2 SI-IEETSSl-1EET 2 F gs III

IN V EN TOR.

Patented Nov. 4, 1 952 UNITED STATES PATENT OFFICE VALVE UNIT FOR INTERNAL-COMBUSTION ENGINES 7 Claims.

This invention relates to valves for. engines and more particularly to .fuel. intake valves for two-cycle internal combustion engines which re.- ceive the fuel lubricating oil and air mixture into the crankcase during one stroke of the piston and transfer the charge within the crankcase to the cylinder during the opposite stroke of the piston.

A principal object of the invention is to'effect a greater turbulence of the fuel and air entering the crankcase and thereby obtain a more complete vaporization of the fuel for optimum operating eificiency of the engine.

Another object is to provide a greater turbulence of the mixture passing from the carburetor into the crankcase or other part of the engine to insure the full lubrication of. all the parts operating in the crankcase.

These and other objects and advantages of the invention are accomplished by employing a plurality of reed valves disposed in angular relation with one another to effect a swirling action for the fuel mixture entering the crankcase.

An embodiment of the invention is illustrated in the accompanying drawings in which:

Figure l is a side elevation of an engine with parts broken away and sectioned to show the construction thereof;

Fig. 2 is a plan view of the engine shown in Fig. l with parts broken away and sectioned to show the construction thereof;

Fig. 3 is a detailed view of the reed valve arrangement as employed in the engine shown in Figs. 1 and 2;

Fig. 4 is a perspective view of a part of the reed plate illustrating the operation of one set of the reed valves;

Fig. 5 is a cross-section taken in a plane longitudinally of one of the valves and normal to the plate of Fig. 3 showing the valve closed; and

Fig. 6 is a view similar to Fig. 5 showing the valve open.

While the invention is adapted to be employed in any two-cycle engine the drawings illustrate the engine for an outboard motor and which is carried by the hollow drive shaft housing 2, shown only in part, which receives and provides for the discharge of the engine exhaust gases.

The engine includes the crankcase 3 mounted on housing 2 and the two opposed cylinder blocks 4 secured to opposite sides of crankcase 3 and mounted on housing 2.

The two cylinders 5 in each block 4 carry the pistons 6 which reciprocate therein. The connecting rods 1 connect pistons E and the crankshaft-8 extending; vertically throu h. h c nk.-

case. Separate crank throws 9 for each-rod 1 are. arranged; so that the two upper and two; lower pistons reciprocat in opposite directions. The circular divider l0 forming part of crankshaft assembly 8 fits within the central wall ll of crankcase 3 to divide the same into separate upper and lower chambers l2.

Thev exhaust ports I3 for each of cylindersg5 open into chambers l4 formed in. each block 4. Each chamber l4 communicates with housing 2 for the discharge of the exhaust gases.

The intake ports l5 for each of cylinders 5 are spaced substantially oppositely of ports [3 and communicate through respective transfer passages IS in blocks 4 with the corresponding upper or lower chamber l2 of the crankcase.

The carburetor having the air intake l8 receives the fuel andlubricating oil from a tank, not shown, through the fuel line I9. The carburetor carried by the manifold 26 connected to crankcase 3 is disposed adjacent one of the cylinder blocks 4 and communicates through mani- V fold 20 with both upper and lower chambers l2.

The manifold 20 is bolted to the side of crankcase 3 with the reed plate 2| to be described disposed therebetween.

Each reed valve 22 carried by plate 2| includes a flat, flexible thin metal reed 23 secured to the crankcase side of plate 2| and normally disposed flat against the plate to cover and close a corresponding hole 24 in the plate. The non-flexible metal rocker 25 is disposed on the back side of reed 23 oppositely of plate 2|. The screws 26 extending through rockers 25 and reeds 23 secure both to plate 2 I.

Each of rockers 25 is secured to plate 2| at one end and curves inwardly of the crankcase away from plate 2|. Each of reeds 24 is secured between rocker 25 and plate 2| allowing the opposite end of the 'reedsto flex easily between plate 2| and the rocker in opening and closing. Holes 24 are of oblong lateral dimensions as shown for the most efficient operation with reeds 23 and are preferably milled in plate 2| with fully rounded ends and with the outwardly facing chamfered edges 21.

The size of each hole 24 and reed 23 should be determined by the requirements of the engine and the number of valves 22 employed. The specifications of the reeds should provide for easy opening of the reeds without fluttering and for the quick and positive seating of the reeds on plate 2| in closing. The length of each reed 23 is de- 3 termined generally by the flexibility of the metal of the reed and the extent of the opening required.

The fixed end of each reed 23 is secured to plate 2| by bolts 26 in line with the ends of the corresponding holes. The free end of each reed is dimensioned to cover the corresponding hole and overlap plate 2| on each side and at one end of hole 24 just sufficiently to provide the necessary seating and cushioning area for the reed when closed by pressures within the crankcase.

Rockers 25 serve to limit and distribute the flexing stresses of the reeds throughout their length. The rockers are curved with a suitable radius in such a manner so that as the reed is opened by the pressure and flow of gas through the valve and closes, the line of marginal contact between the reed and rocker moves uniformly toward and back from the outer end of the rocker. The rockers are dimensioned as to be wholly disposed behind the reeds and not interfere with movement of the fuel mixture through the valves.

The number of valves to be employed for each piston 6 and chamber l2 may vary although four arranged as shown is found to be the most practical in view of the dimension limitations of the engine shown.

In the intake cycle of each piston 6 of engine I, the greater pressure on the area of the respective reeds Etexposed by holes 2 forces the reeds against rockers 25 to open the valves. The fuel mixture admitted by the opened valves passing through the holes impinges the reeds and is deflected in the direction angular to plate 2| indicated generally by the arrow 28 in Fig. 6.

The four valves 22 for each piston 6 are arranged on plate 2! generally about theaxis 29 normal to plate 2i and extending through the approximate center of the respective chamber l2. The four valves of each group are disposed with respect to each other and the respective axisZfi to deflect the fuel mixture passing into the crankcase in a fixed angular relation to the axis.

In the normal operation of engin 3 the rotation of crankshaft 8 within chambers 12 induces a corresponding rotation of the fuel within the chambers which tends to concentrate the fuel in certain locations within the chambers and to prevent the fuel from reaching and lubricating certain portions of the moving parts within the crankcase. The fuel and air mixture passing through the openings of each group of valves 22 moves rotationally into the respective chamber with a swirling or spiral movement as indicated generally by the arrows 28 in Fig. 4 and about an axis 29 at right angles to the axis of the rotational movement of the fuel Within the crankcase as indicated generally by the arrows 30 in Fig. 4. The intersecting directions of rotational movements creates a particularly turbulent condition within the crankcase which effects a more complete vaporization of the fuel from the carbureton The spiraling streams of fuel mixture passing into the chambers at various angles reaches all sides and parts of the crankshaft rotating therein and effects generally a more thorough distribution of the lubricating oil to the other operating parts of the engine.

Various embodiments of the invention may be employed within the'scope of the accompanying claims.

I claim:

1. In a two-cycle internal combustion engine having a crankcase with an inlet for receiving the fuel mixtur prior to transfer of the mixture 4 to the engine cylinder, a reed valve plate and reed valves for said plate arranged thereon and disposed across the inlet to the crankcase to admit the mixture in paths defining a vortex Within the crankcase obtaining a turbulence of the mixture.

2. A two-cycle internal combustion engine comprising a crankcase receiving the combustion .lubricating oil mixture, a reed valve plate disposed across the inlet to said' crankcase, and a plurality of reed valves for said plate disposed, to admit the mixture to the crankcase in angularly related streams about an axis and to effect a swirling motion of the mixture within the crankcase for the vaporization of the fuel and th distribution of the lubrication oil throughout the crankcase.

3. An intake valve unit for an internal combustion engine comprising a plurality of reed valves arranged about an axis extending in the direction of flow of the intake gases and having openings disposed to direct the .intake gases cir cularly about said axis and in angular relation thereto.

4. In a reed valve unit, a plurality of reed valves disposed about an axis in angular relation thereto and operating in correlation to obtain a swirling of the fluids after passing therethrough for more effectively mixing the fluids.

5. In a two-cycle internal combustion engine having a crankshaft and a crankcase with an inlet for receiving the fuel mixture prior to transfer of the mixture to the engine cylinder, a plurality of interspaced reed valves disposed in one wall of said crankcase and providing openings radially spaced from and in fixed relation to an axis substantially intersecting at right angles the axis of said crankshaft.

6. In a two-cycle internal combustion engine having a crankshaft and a crankcase with an inlet for receiving the fuel mixture prior to trans fer of the mixture to the engine cylinder, at plurality of interspaced reed valves disposed in one wall of said crankcase to admit the mixture to the crankcase in angularly related streams about an axis at right angles to the axis of said crankshaft.

7. A two-cycle internal combustion engine comprising a crankshaft, a crankcase for said crankshaft adapted to receiving the combustion fuel and lubricating oil mixture, a reed valve plate disposed across the inlet to said crankcase, and a plurality of reed valves for said plate disposed about an axis in angular relation thereto and to the axis of said crankshaft to provide intersecting rotational movements of the fuel within the crankcase for the more complete vaporization of the fuel and the distribution of the oil throughout the crankcase for the more thorough lubrication of the engine.

E. CARL KIEKHAEFER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name 7 Date 1,130,526 Laurin Mar. 2, 1915 1,194,722 Davol Aug. 15, 1916 1,407,586 Setz Feb. 21, 1922 1,972,805 Vanni Sept. 4, 1934 FOREIGN PATENTS Number Country Date 483,725 Germany of 1929 

